Apparatuses for intravenously infusing drugs to a patient are well known and heavily used during many medical procedures. Infusion apparatuses are characterized by having at least one drug dosage in a container, pumping means, a liquid conduit for conveying a stream of liquid from the container to the vein, and means for penetrating the body and injecting the drug into the vein. An additional fluid container is provided, to hold the fluid which is mixed with the drug and carries the drug to the vein. Apparatuses for timely supplying one of a plurality of drugs to a patient are also known, and such apparatuses are normally provided with a microcontroller for controlling the operation of the device, and with display and keyboard means for programming the apparatus in order to perform the desired sequence of operations with the desired timing. Further, a system for centrally controlling a plurality of infusion apparatuses has lately been developed. Such systems enable a member of the medical personnel to simultaneously manage and control the proper operation of several infusion apparatuses, wherein each particular apparatus can be separately programmed for timely providing one or more of a plurality of different drug dosages to a patient. The system includes a data connection such as by a data bus or a serial connection between a plurality of apparatuses and between them and a central PC. The programming of the system can be carried out either locally in each apparatus, or centrally by the personnel controller at the main PC.
An infusion apparatus for timely providing one of a plurality of drug dosages to a patient is disclosed in U.S. Pat. No. 5,317,506, and schematically shown in FIG. 1. The apparatus comprises a processor 1 for regulating the operation of the apparatus, and a plurality (normally up to 5) of drug vials 10. Each particular drug vial is connected to its dedicated infusion pump 21, and each pump outlet 8 is coupled to a main conduit 6. The main conduit 6 may, in some cases, be included within a component known as a "connector". Said connector has a plurality of individual fluid input ports, all leading to one main channel, which in turn leads to one fluid output port. Throughout the invention it should be understood that whenever the term "connector" is used, it refers to a component which routes fluid from plurality of input ports each one connected to a fluid channel, to one output channel. The main conduit 6 delivers the selected drug to the patient, mixed with fluid coming from fluid container 7, via conduit 9. In said apparatus each infusion pump is controlled by the main processor 1, and is independently operable to infuse a medication into the vein of the patient in accordance with a programmed procedure. Means are also provided for enabling the operation of only one infusion pump at any given time. The said apparatus suffers from a major drawback, viz. it requires the use of a separate infusion pump for each particular drug channel (the term "drug channel", when used herein, refers to a path followed by a drug from a particular drug vial to the patient). Hence, the apparatus is relatively complex, cumbersome and expensive.
U.S. Pat. Nos. 5,378,231 and 4,696,671 disclose another type of n-channel, programmable drug and fluid delivery apparatus, which comprises an Infusion Pump Unit (hereinafter referred to also as IPU). The IPU accommodates a plurality of disposable pumping cassettes 44, each cassette serving one drug channel. The cassettes (best described in U.S. Pat. No. 4,696,671), which are complicated in their structure and relatively expensive, should be replaced and disposed of when connecting the infusion apparatus to a new patient, or periodically for the same patient. Further, each cassette requires for its operation dedicated motor means and driver means, and therefore, a plurality of motors and drivers are required. The apparatus, as shown in FIG. 2, comprises a plurality of drug vials 10 and one fluid container 7. While operative, the apparatus infuses at a predetermined time one selected drug, mixed with fluid from container 7, to the patient. The apparatus has n pumping channels 4, wherein each channel operates independently, and is controlled and concurrently monitored by processor (PC) 1. The main conduit 16 of the apparatus may be connected to a manifold or directly to the patient. As shown, the apparatus comprises only one IPU, having a plurality of pumping cassettes 44. Each cassette within the drug channel can be accessed (e.g., in U.S. Pat. No. 5,378,231) by lifting a protective hood. While in use, it is recommended that the hood be locked in order not to interrupt the proper operation of the device and to prevent removal of drugs. However, each pumping cassette is activated by a motor which is attached to gear means for reducing the motor revolutions, and each particular motor is driven by a dedicated driver. Therefore, the apparatus of FIG. 2 requires a plurality of motors, drivers and gear means. Further, sterility considerations require the frequent replacement of the relatively expensive cassettes, connector (when available), and conduits. Hence, the apparatus is cumbersome, costly, and requires frequent and complicated service for its operation.
It should be noted here that current regulations in essentially all countries require the disposal of a complete infusion set to obtain a new one, for any new patient. An infusion set consists of all the parts that are in direct contact with the fluid infused to the patient. In the apparatus of FIG. 1, those parts are the drug vials, connector and the conduits. In the apparatus of FIG. 2, the administration set consists of the drug vials, the conduits, the cassettes and connector (when exists).
It is an object of the invention to provide a multi-channel apparatus for providing infusion of several medications to a patient, which does not suffer from the abovementioned drawbacks.
It is another object of the invention to provide an infusion apparatus which is more reliable and of lower cost.
It is a further object of the invention to provide an apparatus which is much easier to serve, program, and maintain from the prior art ones.
It is still a further object of the invention to eliminate the cost and time consumption involved in the replacement of disposable elements which are part of each administration set, and more particularly, to eliminate the use of a disposable cassette as an essential part of each infusion channel.